Merge pull request #542 from thefab/unused_commit

unused import
bad comment (before/after_kill never existed publicly, replaced by
before/after_signal)
Merge pull request #544 from thefab/comment_fix

bad comment (before/after_kill never existed publicly, replaced by before/after_signal)
Initial version of the CommandReloader plugin
Follow test naming convention for plugins
Fix interpretation of loop_rate option
Add missing quote
Check cmd path changes
Explicitly return False from is_modified
Fix plugin example

 * fix constuctor
 * disable output buffering so that events get logged immediately
 * add a new line to log messages for readability
Add config to example command line

Otherwise the example plugin won't start
Merge pull request #547 from amarandon/command_reloader

Initial version of the CommandReloader plugin
Merge pull request #550 from amarandon/fix_plugin_doc

Fix plugin doc
Fix CommandReloader plugin doc

 * default loop_rate is 1 second
 * we also check cmd path
Merge pull request #551 from amarandon/command_reloader

Fix CommandReloader plugin doc
make sure we call basicConfig() prior to the first call
plugins are also watchers - fixes #552
Merge branch 'async_experiment' of https://github.com/thefab/circus into thefab-async_experiment
moved some code into TestCircus for reusing
started to make test_arbiter async